Radio communication system, base station, mobile station, communication control method, and computer readable medium

Abstract

A first base station ( 1 ) is configured to send, to a second base station ( 2 ), first configuration information that is necessary to establish a data bearer and a data radio bearer in the second base station ( 2 ) for a C/U-plane split scenario. Further, the first base station ( 1 ) is configured to send, to a third base station ( 3 ), configuration information (e.g., LPN information) regarding the data bearer established in the second base station ( 2 ) when a mobile station ( 4 ) moves from a first cell ( 10 ) to a third cell ( 30 ) (S 103 and S 104 ). It is thus, for example, possible to contribute to a reduction in wasted signaling when a UE moves between cells in the C/U-plane split scenario.

The invention claimed is: 
     
       1. A method for a first base station, the method comprising:
 transmitting, to a second base station, a first message requesting the second base station to configure a user plane (U-plane) path, wherein the U-plane path connects a data transfer apparatus through the second base station to a user equipment (UE), wherein the first message includes:
 an identifier of the U-plane path; 
 a QoS information of the U-plane path; 
 an address of the data transfer apparatus; and 
 a first Tunnel Endpoint Identifier (TEID) on the data transfer apparatus's side, the first TEID corresponding to the U-plane path; and 
 
 transmitting, to a third base station, a second message requesting a handover of a control plane (C-plane) path from the first base station to the third base station without changing the U-plane path, wherein the C-plane path connects a mobility management apparatus through the first base station to the UE, wherein the second message includes:
 an identifier of the second base station; 
 the identifier of the U-plane path; 
 the QoS information of the U-plane path; 
 the address of the data transfer apparatus; and 
 the first TEID. 
 
 
     
     
       2. The method according to  claim 1 , wherein the first message includes a security key. 
     
     
       3. The method according to  claim 1 , wherein the first message includes a configuration of a data radio bearer (DRB), the DRB corresponding to the U-plane path. 
     
     
       4. The method according to  claim 1 , wherein the second message includes a configuration of a data radio bearer (DRB), the DRB corresponding to the U-plane path. 
     
     
       5. The method according to  claim 3 , wherein the configuration of DRB includes a PHY layer configuration and a MAC sublayer configuration. 
     
     
       6. The method according to  claim 1 , wherein the second message includes a second TEID on the second base station's side, the second TEID corresponding to the U-plane path. 
     
     
       7. The method according to  claim 1 , further comprising transmitting, to the UE, a third message indicating a handover of the C-plane path from the first base station to the third base station without changing the U-plane path. 
     
     
       8. The method according to  claim 7 , wherein the third message indicates that continuation of the U-plane path provided by the second base station. 
     
     
       9. The method according to  claim 1 , further comprising receiving, from the third base station, a first response to the second message. 
     
     
       10. The method according to  claim 1 , further comprising transmitting, to the second base station, information indicating the C-plane path transferring from the first base station to the third base station. 
     
     
       11. The method according to  claim 1 , wherein the identifier of the U-plane path is E-RAB ID. 
     
     
       12. The method according to  claim 1 , wherein
 the data transfer apparatus is S-GW, and the mobility management apparatus is MME. 
 
     
     
       13. The method according to  claim 1 , wherein a first tunnel of the first TEID is a S1-U interface between the second base station and the data transfer apparatus. 
     
     
       14. The method according to  claim 1 , wherein an S1-MME interface for the UE is terminated in the first base station or the third base station, and an S1-U interface for the UE is terminated in the second base station. 
     
     
       15. The method according to  claim 14 , wherein the S1-MME interface is used for control plane, and the S1-U interface is used for user plane. 
     
     
       16. The method according to  claim 14 , wherein the S1-MME interface and the S1-U interface are used simultaneously. 
     
     
       17. A first base station comprising:
 a memory storing instructions; and 
 at least one hardware processor configured to process the instructions to: 
 transmit, to a second base station, a first message requesting the second base station to configure a user plane (U-plane) path, wherein the U-plane path connects a data transfer apparatus through the second base station to a user equipment (UE), wherein the first message includes:
 an identifier of the U-plane path; 
 a QoS information of the U-plane path; 
 an address of the data transfer apparatus; and 
 a first Tunnel Endpoint Identifier (TEID) on the data transfer apparatus's side, the first TEID corresponding to the U-plane path; and 
 
 transmit, to a third base station, a second message requesting a handover of a control plane (C-plane) path from the first base station to the third base station without changing the U-plane path, wherein the C-plane path connects a mobility management apparatus through the first base station to the UE, wherein the second message includes:
 an identifier of the second base station; 
 the identifier of the U-plane path; 
 the QoS information of the U-plane path; 
 the address of the data transfer apparatus; and 
 the first TED. 
 
 
     
     
       18. A method for a third base station, the method comprising:
 receiving, from a first base station, a first message requesting a handover of a control plane (C-plane) path from the first base station to the third base station without changing a user plane (U-plane) path, wherein the C-plane path connects a mobility management apparatus through the first base station to a user equipment (UE), wherein the U-plane path connects a data transfer apparatus through a second base station to the UE, 
 wherein the first message includes:
 an identifier of the second base station; 
 an identifier of the U-plane path; 
 a QoS information of the U-plane path; 
 an address of the data transfer apparatus; and 
 a first Tunnel Endpoint Identifier (TEID) on the data transfer apparatus's side, the first TEID corresponding to the U-plane path. 
 
 
     
     
       19. The method according to  claim 18 , further comprising receiving, from the UE, a second message indicating a handover of the C-plane path from the first base station to the third base station without changing the U-plane path. 
     
     
       20. The method according to  claim 18 , further comprising transmitting, to the second base station, information indicating the C-plane path transferring from the first base station to the third base station. 
     
     
       21. The method according to  claim 20 , wherein the information is information about the third base station. 
     
     
       22. A third base station comprising:
 a memory storing instructions; and 
 at least one hardware processor configured to process the instructions to:
 receive, from a first base station, a first message requesting a handover of a control plane (C-plane) path from the first base station to the third base station without changing a user plane (U-plane) path, wherein the C-plane path connects a mobility management apparatus through the first base station to a user equipment (UE), wherein the U-plane path connects a data transfer apparatus through a second base station to the UE, wherein the first message includes: 
 an identifier of the second base station; 
 an identifier of the U-plane path; 
 a QoS information of the U-plane path; 
 an address of the data transfer apparatus; and 
 a first Tunnel Endpoint Identifier (TEID) on the data transfer apparatus's side, the first TEID corresponding to the U-plane path.